1. Field of the Invention
This invention relates to wire strippers generally and, more particularly, to a wire stripper that is versatile, long-lasting, convenient to use, and inherently produces circular cuts.
2. Background Art
"Wire" usually refers to a central electrical conductor surrounded by insulation, while "cable" usually refers to a central conductor surrounded by insulation, with a second conductor of foil or braid surrounding the first layer of insulation and a second layer of insulation surrounding the second conductor. "Wire" and "cable" at times may be used herein interchangeably, as will be clear from the context.
One type of wire stripper long known in the art comprises a pair of opposed blades having handles at one end thereof, which handles are pivotally attached together between the blade ends and the handle ends. The blades have opposed, aligned pairs of sharp notches along their lengths such that when the blades are manually urged together, a selected pair of notches closes about, and cuts through, the insulation on a wire. Rotating the stripper in its closed position in a circular motion of at least 180 degrees about the wire in a plane perpendicular to the axis of the wire severs the insulation and allows it to be pulled off the end of the wire. The pairs of notches are variously sized to cut insulation on wires or cables of several different diameters. While this type of stripper is somewhat satisfactory, it is inconvenient to use, in part, because of limitations of a human arm and wrist in rotating the stripper. The number of different diameters which can be accommodated is limited, a fairly unobstructed space around the wire or cable is required, and the cutting edges of the notches have a relatively limited life. A further limitation is that to make two cuts--required, for example, with a cable having a braided or foil sheath under a first layer of insulation--it is necessary to open and reposition the stripper. Additionally, it is difficult to rotate the stripper in a true circle.
Another type of stripper includes a tool having two elongate body parts, pivotally joined at one end and normally latched together. Inserted in the body is a cassette having two or three straight blades adjusted to make cuts of selected depths. To use the stripper assembly, the tool is unlatched, the body parts swung apart, a cable inserted along an axis perpendicular to the plane in which the hinged parts move, and the body closed and latched. A circular opening formed at one end of the body allows insertion of a finger for rotating the tool around the wire to complete the stripping operation. Changing cassettes and blade heights allows a range of cable sizes to be stripped. This system overcomes some of the limitations of the device described above, but at the expense of time lost in the procedure of inserting the cable in the body. A major limitation is that, unless the person using the tool is very careful, there is a tendency to move the tool elliptically rather than circularly, resulting in poor cuts. This is especially a problem when working with small size cables. Additionally, more than a minimum amount of space is required around the cable to perform the cutting motion and the straight blades employed have relatively limited life.
A further type of stripper has straight blades positioned in an aperture at one end of an elongate body, with a finger hole, as above, disposed at the opposite end of the body. The aperture is opened by pulling the end of the body with the finger hole away from the aperture end which allows insertion of the cable. The tool is then rotated around the cable, as above. If a second cut is desired, then the aperture is opened and the cable respositioned for the second cut. The operation is again repeated if a third cut is desired. This stripper has the advantage of ease of insertion of the cable, but requires repositioning for multiple cuts, requires more than a minimum amount of space for operation, its straight blades have a relatively limited life, and each size cable requires a different tool. Also, the stripper tends to produce elliptical cuts.
Accordingly, it is a principal object of the present invention to provide a wire stripper which can accommodate a range of cable diameters.
Another object of the present invention to provide a wire stripper which can make multiple cuts in one step.
A further object of the present invention is to provide a wire stripper which is compact and requires a minimum of space around a cable for the cutting operation.
An additional object of the present invention is to provide a wire stripper into which a cable may be easily inserted in a single step.
Yet another object of the present invention is to provide a wire stripper which has blades having a substantially longer life than straight blades.
Yet a further object of the present invention is to provide a wire stripper which is easily and economically manufactured.
Yet an additional object of the present invention is to provide a wire stripper which inherently produces circular cuts.
Other objects of the present invention will, in part, be obvious, and will, in part, be apparent from the following description and the accompanying Drawing.